Final answer:
The potential energy possessed by the mass is 1225 J.
Step-by-step explanation:
The potential energy (PE) possessed by the mass can be calculated using the equation PE = mgh, where m is the mass (250 kg), g is the acceleration due to gravity (approximately 9.8 m/s^2), and h is the height (0.5 m). Substituting the given values, we have PE = 250 kg × 9.8 m/s^2 × 0.5 m = 1225 J. Therefore, option a) 1225 J is the correct answer.